Seminar: Molecular clocks of human evolution - Dr. Priya Moorjani, Columbia Univeristy
Seminar | February 8 | 3:30-4:30 p.m. | 125 Li Ka Shing Center
Abstract: One of the most fundamental discoveries in evolutionary biology is the molecular clock: the observation that changes to the genome due to mutation and recombination occur steadily with time. Thus, the accumulation of neutral substitutions (i.e., changes with no fitness effects) over generations provides a record of the time elapsed and hence an evolutionary clock that can be used to characterize past events. Yet, across mammalian phylogenies, substantial variation in rates has been documented. In this talk, I will discuss two related ideas: understanding the variation in molecular clocks across primates, and developing methods to reliably apply molecular clocks for dating evolutionary events. This work includes the use of genetic data from ancient specimens and extant primates to characterize the differences in mutation landscape across closely related species and to date ancient specimens by measuring the missing evolution in ancient genomes compared to present-day samples, as well as to infer the evolutionary history of human specific duplications (i.e., gene copies present in humans but not in other primates). These analyses have provided insights about the timeline of human evolution, as well as helped to uncover the determinants of mutation rate and learn about the dynamics of human adaptation.